diff --git a/free-programming-books.md b/free-programming-books.md
index c1b37ef3313150b57fe32c2891307d43578acf6e..5982bafd7c8fd595ee2e6978a03174fd6df2eb28 100755
--- a/free-programming-books.md
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@@ -497,7 +497,7 @@
 * [Introduction to Design Patterns in C++ with Qt](http://ptgmedia.pearsoncmg.com/images/9780131879058/downloads/0131879057_Ezust_book.pdf)
 * [Data Structures and Algorithms with Object-Oriented Design Patterns in C++](http://www.brpreiss.com/books/opus4/index.html)
 * [The Boost C++ libraries](http://en.highscore.de/cpp/boost)
-* [C++ Cookbook](http://staff.ppu.edu/dkhalid/O'Reilly%20-%20C++%20Cookbook%20(2007).pdf)
+* [C++ Cookbook](http://staff.ppu.edu/dkhalid/O'Reilly%20-%20C++%20Cookbook%20%282007%29.pdf) (PDF)
 * [The Rook's Guide to C++](http://rooksguide.org/2013/11/26/version-1-0-is-out/) (PDF)
 
 ###Clojure